It is a gift and I’d make someone VERY happy.  All I could get from her is that the book probably from 1970’s, maybe earlier. The main character was a boy with a dog, there was also a girl in book that a cat. Book went from colorless to having colors (or maybe dull to colorful) as more colors appeared, the boy became more happy. Flowers became colorful, each petal would have different fabric in different colors.  Other items changed colors too and they were all patchwork-looking.  

I know this isn’t a ton to go from, but it is a unique-sounding book, so my fingers are crossed.  Many thanks, you may be my new hero if you can assist.